An absorbent article such as a disposable diaper is an article that absorbs urine discharged from the wearer with an absorber using an absorbing component such as wood pulp and super absorbent polymer (hereinafter also referred to as “SAP”), and receives feces (solid excretion).
The absorbent article desirably has sufficient urine absorbing ability so as to withstand long-time use and so as to prevent urine leakage. Therefore, a method of increasing the amount of absorber is normally adopted to provide the sufficient urine absorbing ability to the absorbent article.
However, the following problems still remain even if the amount of absorber is simply increased. First, the utilization efficiency of the absorber degrades. In other words, only a portion of the absorber close to the area where the urine is discharged absorbs urine, and another portion of the absorber distant from the area where the urine is discharged is not utilized to absorb urine, and thus the ratio of the portion utilized to absorb urine to the entire amount of absorber lowers. Next, there is a problem that, as the amount of absorbed urine increases, in particular, as the amount of absorbed urine approaches the design limit of the absorbing capacity, the amount of returning urine from the absorber to the top sheet, that is, the rewet amount increases. If the rewet amount is large, the moisture amount existent on the body surface of the wearer at and after discharge of urine increases, thereby degrading the wearing feeling as the body surface easily gets humid and becoming the main cause of so-called diaper rash.
In recent years, various absorbent articles, which are not only excellent in urine absorbing ability but also aiming to prevent problems such as stuffiness, rash, smell, and the like are proposed. The absorbent articles aiming to allow easy and hygienical disposal after use are also proposed.
For example, Patent Documents 1 to 4 describe so-called urine/feces separating diapers such as the absorbent article aiming to separately accommodate urine and feces by providing each opening for urine at a front part and for feces at a rear part of the front surface of the absorbent article, and the absorbent article aiming to prevent mixing of urine and feces by providing a partition member (urine/feces separating member) in the vicinity of a central part of the absorbent article.
However, if the front part is dedicated to urine and the rear part is dedicated to feces as in the absorbent articles described in Patent Documents 1 to 4, it is difficult to arrange the absorber in an amount that provides sufficient urine absorbing ability. In particular, the urine-absorbing ability is important as the number of urine discharges is actually greater than the number of feces discharges.
Patent Document 1 JP 6-327715 A
Patent Document 2: JP 9-510384 A
Patent Document 3: JP 9-510385 A
Patent Document 4: JP 11-113958 A